title: Transcriptional reprogramming and stimulation of leaf respiration by elevated CO2 concentration is diminished, but not eliminated, under limiting nitrogen supply.
abstract: Plant respiration responses to elevated CO2 concentration ( [CO2 ] ) have been studied for three decades without consensus about the mechanism of response. Positive effects of elevated [CO2 ] on leaf respiration have been attributed to greater substrate supply resulting from stimulated photosynthesis. Negative effects of elevated [CO2 ] on leaf respiration have been attributed to reduced demand for energy for protein turnover assumed to result from lower leaf N content. Arabidopsis thaliana was grown in ambient (370 ppm) and elevated (750 ppm) [CO2 ] with limiting and ample N availabilities. The stimulation of leaf dark respiration was attenuated in limiting N (+12%) compared with ample N supply (+30%). This response was associated with smaller stimulation of photosynthetic CO2 uptake, but not interactive effects of elevated CO2 and N supply on leaf protein, amino acids or specific leaf area. Elevated [CO2 ] also resulted in greater abundance of transcripts for many components of the respiratory pathway. A greater transcriptional response to elevated [CO2 ] was observed in ample N supply at midday versus midnight, consistent with reports that protein synthesis is greatest during the day. Greater foliar expression of respiratory genes under elevated [CO2 ] has now been observed in diverse herbaceous species, suggesting a widely conserved response.
authors.affiliation: Department of Plant Biology and Institute for Genomic Biology, University of Illinois Urbana-Champaign, 1402 Institute for Genomic Biology.
authors.forename: R J Cody
authors.initials: RJ
authors.lastname: Markelz
authors.forename: Lisa X
authors.initials: LX
authors.lastname: Lai
authors.forename: Lauren N
authors.initials: LN
authors.lastname: Vosseler
authors.forename: Andrew D B
authors.initials: AD
authors.lastname: Leakey
mesh_terms: D000704:Analysis of Variance; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000502:physiology* / Q000528:radiation effects; D018533:Biomass; D002245:Carbon Dioxide / Q000494:pharmacology*; D019069:Cell Respiration / Q000187:drug effects / Q000235:genetics / Q000528:radiation effects; D002952:Citric Acid Cycle / Q000187:drug effects / Q000528:radiation effects; D004579:Electron Transport / Q000187:drug effects / Q000528:radiation effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000528:radiation effects; D017343:Genes, Plant; D008027:Light; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D009584:Nitrogen / Q000494:pharmacology*; D010788:Photosynthesis / Q000187:drug effects / Q000528:radiation effects; D018515:Plant Leaves / Q000187:drug effects / Q000235:genetics / Q000502:physiology* / Q000528:radiation effects; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013213:Starch / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects* / Q000528:radiation effects
chemical_list: D012333:RNA, Messenger; D002245:Carbon Dioxide; D013213:Starch; D009584:Nitrogen
keywords: Arabidopsis; climate change; genomic; respiratory metabolism; transcriptome